1. Field of the Invention
The present invention relates to a telephone line lockout device and more particularly pertains to permitting controlled access of telephone line from one of a given number of extension telephones coupled thereto when each extension telephone is controlled with the same with a telephone extension controller.
2. Description of the Prior Art
The use of telephone line controllers is known in the prior art. More specifically, telephone line controllers heretofore devised and utilized for the purpose of permitting access to telephone lines are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
By way of example, U.S. Pat. No. 4,000,376 discloses a telephone privacy device. U.S. Pat. No. 4,647,723 to Voorhies discloses a circuit for detection of off-hook condition of extension telephones. U.S. Pat. No. 4,747,128 to Chan et al. discloses a telephone privacy protector. U.S. Pat. No. 4,899,372 to Wahi et al. discloses a multi use telephone extension control circuit and device providing lockout for privacy. U.S. Pat. No. 4,985,916 to Tachuk et al. discloses a party line converter.
While these devices fulfill their respective, particular objective and requirements, the aforementioned patents do not describe a telephone line lockout device that allows a selected extension telephone to control a telephone line that is connected to a plurality of other extension telephones.
In this respect, the telephone line lockout device according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of permitting controlled access of telephone line from one of a given number of extension telephones coupled thereto when each extension telephone is controlled with the same.
Therefore, it can be appreciated that there exists a continuing need for new and improved telephone line lockout device which can be used for permitting controlled access of telephone line from one of a given number of extension telephones coupled thereto when each extension telephone is controlled with the same. In this regard, the present invention substantially fulfills this need.